PTAB

IPR2017-01167

Pfizer Inc v. Biogen Inc

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Treatment of Aggressive Non-Hodgkin's Lymphoma with Anti-CD20 Antibody
  • Brief Description: The ’244 patent claims a method for treating a specific patient population—individuals over 60 years old with diffuse large B-cell lymphoma (DLCL) and bulky disease (tumor > 10 cm)—by administering a combination of an unlabeled chimeric anti-CD20 antibody and CHOP chemotherapy. Claim 2 specifies the antibody is rituximab.

3. Grounds for Unpatentability

Ground 1: Claims 1-2 are obvious over Shipp and Link in view of McNeil.

  • Prior Art Relied Upon: Shipp (a 1995 journal article), Link (a May 1998 meeting abstract), and McNeil (a February 1998 journal article).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Shipp taught using high-dose CHOP chemotherapy to effectively treat patients with intermediate- or high-grade non-Hodgkin's lymphoma (NHL), including DLCL, accompanied by bulky disease (tumor ≥ 10 cm). The Shipp study included patients aged 60 or older. Separately, Link disclosed a study combining rituximab with CHOP for intermediate- and high-grade NHL, reporting higher response rates with a toxicity profile similar to CHOP alone. Petitioner asserted these references collectively disclose all elements of the challenged claims.
    • Motivation to Combine: Petitioner contended that the motivation to combine was explicitly provided by the prior art, particularly McNeil. McNeil highlighted that elderly patients (over 60) had poorer outcomes with standard CHOP therapy due to higher toxicity and identified a clear need for alternative treatments that were more effective but not more toxic. Crucially, McNeil suggested that one such alternative "could be CHOP plus the monoclonal antibody [rituximab]." This direct suggestion, addressing the precise problem of treating elderly patients, provided a clear motivation for a person of ordinary skill in the art (POSA) to combine the CHOP regimen for bulky disease (from Shipp) with the rituximab combination therapy shown to be effective and tolerable (from Link).
    • Expectation of Success: A POSA would have had a reasonable expectation of success. Link demonstrated that the CHOP and rituximab combination was a "tolerable therapy" that "may offer higher response rates" than CHOP alone. Given this data, a POSA would reasonably expect that applying this more effective and equally tolerable regimen to the difficult-to-treat patient population identified by Shipp and McNeil (elderly, with bulky disease) would yield positive results.

Ground 2: Claims 1-2 are obvious over Shipp and Coiffier.

  • Prior Art Relied Upon: Shipp (a 1995 journal article) and Coiffier (a September 1998 journal article).
  • Core Argument for this Ground:
    • Prior Art Mapping: As in Ground 1, Petitioner relied on Shipp for its disclosure of using CHOP chemotherapy to treat patients over 60 with bulky disease. Coiffier was cited for its teaching that rituximab monotherapy was safe and effective in elderly patients with DLCL, demonstrating significant clinical activity with low toxicity. Coiffier studied a patient population with a median age over 60. Together, Petitioner argued these references teach all limitations of claims 1 and 2.
    • Motivation to Combine: The motivation arose from the need to improve treatment for the high-risk population in Shipp without increasing toxicity. Coiffier showed that rituximab was safe and active in elderly patients and explicitly concluded that rituximab "has significant activity in DLCL... and should be tested in combination with chemotherapy in such patients." This direct suggestion provided a strong motivation for a POSA to add rituximab to the standard CHOP therapy taught by Shipp. Petitioner further argued against any "teaching away" by Coiffier. While the Patent Owner had previously argued to the Examiner that Coiffier taught away because rituximab monotherapy was ineffective against very large tumors (>10 cm), Petitioner contended this would motivate a POSA to combine it with an effective therapy like CHOP, not abandon it.
    • Expectation of Success: A POSA would have reasonably expected success because Coiffier established rituximab's safety and efficacy in the claimed elderly patient population, and Shipp established the baseline efficacy of CHOP in patients with bulky disease. Coiffier's explicit suggestion to test the combination would have further bolstered the expectation that combining the two known treatments would be a fruitful and predictable path to improving outcomes for these patients.

4. Relief Requested

  • Petitioner requests the Board institute an inter partes review and cancel claims 1-2 of the ’244 patent as unpatentable under 35 U.S.C. §103.